Pony Wars: Doubling The Power Of Our Mustang With Boost & Tuning

By now you know the deal. Our 2017 Mustang GT is battling it out with a 2017 Camaro SS in a competition for pony car supremacy as part of Horsepower Wars. To be frank, our S550 started out at a bit of a disadvantage out of the gate in Pony Wars, as the Camaro had received a number of upgrades as part of a model-year refresh. However, we knew we still had a shot once the mods started piling up.

As you can see from our results, these Coyote engines do not need a whole lot to make a ton of power. — Matt Kesatie, DiabloSport

Those mods, which came in $5,000 and $15,000 installments based on Summit Racing pricing, have really improved the performance level of our first-generation S550. We picked up nearly 50 horsepower at the wheels with the naturally aspirated mods, but we couldn’t go all in on power mods, as the competitions include braking, chassis dyno, drag racing, and road racing.

How would our bolt-on Coyote 5.0-liter engine respond to a ProCharger D-1X and an ample supply of 100-octane fuel? Well, with a custom DiabloSport calibration, it doubled its rear-wheel output with nary an internal modification.

As such, we had to create a well-rounded package. However, knowing that we were starting out with a disadvantage, we had to be strategic about how to mod the car at each level knowing the final score is what really matters. So, our lackluster baselines didn’t matter so much because it’s not where you start, it is where you finish.

To ensure a strong finish, we worked to build a solid foundation with the first round of modifications to set the stage for the real gains at the $15,000 level. Yet, we couldn’t concentrate too heavily on just power gains, so other areas took up a good chunk of the budget. This is where we opted to roll the dice and rely on the Coyote 5.0-liter engine’s inherent boost-friendly nature.

To that end, we left the engine stock, save for our $5,000 bolt-ons, and put all our horsepower money on a ProCharger D-1X tuner kit with a race intercooler upgrade. Supported by just a JMS FuelMax fuel pump voltage booster and a set of DeatschWerks 1,200cc fuel injectors, the stock Gen 2 Coyote was ready to howl.

Of course, adding boost to our combination meant that our existing DiabloSport custom calibration wouldn’t work. As such, we yet again relied on the company’s ace calibrator, Matt Kesatie, to dial in the combination on 100-octane race gas for the drag strip and dyno and dial in a 93-octane cal for our extended runs on the road course.

The inTune i3 Platinum is pre-loaded with dyno-proven calibrations but it is also compatible with DiabloSport’s CMR tuning software, which is used to create custom calibrations.

“Any time you are dealing with a forced induction setup the risk factor goes up. While it is certainly possible for a naturally aspirated combo to be hurt, it is far less likely than with a boosted setup,” Matt explained. “You have to watch fuel trims, air/ fuel ratios, and timing much closer with a boosted setup. Raised cylinder pressures also require different cam timing that a naturally aspirated combo — to both bleed extra pressure yet keep all the boost from going out the exhaust. There is additional transmission tuning needed as well to make sure the gearbox can handle the extra power the engine it putting out.”

There was no need to change up the tuning hardware, however. A DiabloSport InTune i3 Platinum handheld tuner and its companion software got the job done, and since we added it in the first round, didn’t count toward our $15K budget.

“The Diablo software gives you full control over anything you could need in the powertrain control module to make the changes needed for combos such as this,” Matt said. “The InTune allows not only allows you to store multiple tunes in it for various scenarios but it also works as the pass through device for the CMR logging software so you can very closely watch all the parameters I mentioned above, plus many more, to ensure things behave themselves.”

We relied upon DiabloSport’s custom tuning capability to dial in the ProCharger D-1X and supporting hardware on our 2017 Mustang GT.

With the proper hardware and data, the DiabloSport team was able to dial in our combination to not only make great power, but to retain the kind of street manners that make our 2017 Mustang GT a true dual threat.

“There are dozens of things you need to watch when tuning a combo like this. I would have to pick air/fuel ratio and timing as the top ones,” Matt explained.

Obviously those changes worked, as our Mustang picked up a lot of power. In fact, if you’ve been following the Pony Wars saga, you know that we promised to double the output of our combo, and with the help of DiabloSport we did just that with a few ponies to spare.

“The overall combo is very good. It was obviously geared more toward handling and stopping which really works out. As you can see from our results, these Coyote engines do not need a whole lot to make a ton of power. My only thing that I commented on in the videos is I would have liked to seen an aftermarket cat-back exhaust on the car,” Matt said.

So, yes, our Mustang jumped from 402 horsepower to a whopping 809 horsepower at the wheels with just boost, fuel, and tuning. Coyotes certainly love boost, but the question remains whether it will be enough to outduel a Camaro receiving ported heads, a big cam, and the same ProCharger D-1X?

How about them gains? With just boost, custom tuning, and minor fuel system enhancements, our Pony Wars stallion picked up over 400 horsepower and 237 lb-ft of torque at the rear wheels, but will it be enough to best a Camaro with internal engine mods and the same blower?

Both cars will also receive a more conservative 91-octane tune that will allow us to run flat out on the road course safely without buying a cargo ship full of race gas.

“Mainly I concentrated on making it live on the road racing one. Even on the ‘dumbed-down’ tune it still makes more than enough power for what they are doing in the road racing,” Matt explained. “I kept the timing lower and the air/fuel richer to basically manage the cylinder heat better. Try to keep the piston temps down and allow it to survive the long drawn out times where it is at WOT. This is where the air-to-air intercooler comes into play as there is no closed-loop water system that you have to worry about heat soaking and the temps going way up.”

“On the drag race tune [it] was basically the opposite. This combo is capable of a 9-second pass, so being at WOT for 9-10 seconds at a time allows you to get much more aggressive on the calibration,” Matt added. “I basically ‘gave it all its got’ within reason here. There is a bit more left on the table but that’s as far as I’m willing to push it on the fuel that we were using.”

DiabloSport InTune i3 Platinum Features

• 50-state-legal tuning is available

• Can flash multiple vehicles with additional license purchase

• Compatible with Windows, Mac OSX and Linux operating systems

• Disables traction control if desired

• Easy Tune mode simplifies calibrations

• Fast read and write times speed up the process

• Includes dyno-tested preprogrammed calibrations

• Launch control customization

• Logs OBD-II data

• Reads and clears diagnostic trouble codes

• Raises rev and speed limiters if desired

So how will it play out? Pony Wars is getting close to the finish line, so stay tuned to see if our pony car prevails over its archnemesis.

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About the author

Steve Turner

As Executive Editor of FordNXT and Ford Muscle, Steve Turner brings decades of passion and knowledge to Power Automedia. He has covered the world of Ford performance for over 20 years. From the swan song of the Fox Mustang to the birth of the Coyote, Steve had a front-row seat.